CATextLayer rotate?

问题

This should really work, but is not:

CATextLayer* textLayer = [CATextLayer layer];
textLayer.string = @"text";
[textLayer setValue:[NSNumber numberWithDouble:M_PI / 2.f forKey:@"transform.rotation"];
[self addSublayer:textLayer];

in fact, when i print the value at transform.rotation, it shows the correct answer. it just doesn't draw the textLayer rotated!

NSLog(@"rotation %@", [textLayer valueForKey:@"transform.rotation"]);

What am I doing wrong?

回答1:

Try the following code:

textLayer.transform = CATransform3DMakeAffineTransform(CGAffineTransformMakeRotation(M_PI_2));

instead of:

[textLayer setValue:[NSNumber numberWithDouble:M_PI / 2.f forKey:@"transform.rotation"];

回答2:

The CALayer will remember any value you give it. I believe what you have it wrong because you need to rotate with "transform.rotation.z".

来源：https://stackoverflow.com/questions/9269462/catextlayer-rotate